Emergency And Ventilation Override; Ventilation Override; Emergency Override - Trane Symbio 700 Controller Application Manual

Building Automation System Support Sequences
All equipment safeties and limitations will be in-place while the Remote Capacity Control functions are
being leveraged:
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Emergency and Ventilation Override

This feature has two options for initiating an override request, either through the optional hardwired
Ventilation Override terminals, or by initiating a request through the Emergency Override point.
Ventilation Override via the hard-wired binary inputs has priority over Emergency Override.

Ventilation Override

When configured for the Ventilation Override option, applying 24 volts to one of the three Ventilation
Override inputs manually activates Ventilation Override. Three inputs are provided on the Customer
Option Module supporting Ventilation Override functionality:
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If more than one mode is requested at the same time, the Pressurize request will have priority followed
by Purge, and then Exhaust. When Any Ventilation Override mode is active, all heating and cooling is
turned off. For the case where the unit is required to turn Off via hardwired interface, the Equipment
Shutdown binary input is used.

Emergency Override

All units with Symbio™ 700 support the remote Emergency Override command functionality. Within this
point, there are addition enumerations versus the hardware Ventilation Override interface:
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Pressurize, Depressurize, and Purge map to their respective Ventilation Override Modes directly. ,
Emerg_Shutdown and Emerg_Fire are unique to Emergency Override. Both of those are treated as a
remote shutdown request for the equipment.
Equipment Operation
Emergency and Ventilation Override requests/actions will take priority over normal equipment timing
events, such as compressor minimum ON/OFF/Inter-stage timers.
During an Emergency or Ventilation Override sequence, all temperature control algorithms are initialized
to an inactive state until the Emergency or Ventilation Override request is cleared. For each override
request, the unit will operate in a pre-determined state until override requests are cleared.
For detailed unit operation during Emergency or Ventilation Override, refer to the Appendix section of
this document.
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Minimum fan speeds as defined per active capacity will be maintained
Compressor Minimum ON/OFF times will be maintained
All system diagnostics will be maintained.
Pressurize mode
Purge mode
Exhaust mode
1 = EMERG_NORMAL
2 = EMERG_PRESSURIZE
3 = EMERG_DEPRESSURIZE
4 = EMERG_PURGE
5 = EMERG_SHUTDOWN
6 = EMERG_FIRE
ACC-APG002A-EN